Light Diesel versus PCMO. Main difference is?

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739
Location
Australia
I was just wondering what is typically the difference in the formulation of light diesel oils versus regular "passenger car" oils. I know diesel oils are often heavier, like the popular 15W40, but I was looking at a 5W30 low SAPS diesel engine oil today and wondering why it would or wouldn't work fine in a regular petrol engine. BTW. This is the oil that had me wondering: http://www.nulon.com.au/products/Engine_...ife_Engine_Oil/
 
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Messages
28,123
Location
Regina, Saskatchewan, Canada
The one you referenced would probably be fine, with a few considerations. Many HDEOs, even in 10w-30 or 5w-30, even if they are SM or better are not GF-4 or better - they don't have the resource conserving designation. So, it's not the "ideal" choice for someone who has a vehicle under warranty that requires both SM and GF-4 or better. If it meets standards or the vehicle is out of warranty, I wouldn't have a problem with it. My old Audi and F-150 both have specs that are met perfectly by various HDEOs, so I've used them in both vehicles without concern. In my G37 under warranty, requiring 5w-30 SM/GF-4 or better, I'd think twice. As for the differences between the HDEO and the PCMO, the former generally has a different detergent package, higher TBN (though not always the case with low SAPS oil now), and higher ZDDP content. I'm sure there are other differences (like friction modifiers, or lack thereof more likely) that disqualify them from a current ILSAC rating. Others are more knowledgeable about this than I am.
 
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13,382
Location
ROCHESTER, NY
What vehicle are you considering this oil for? I didn't go into each PDF on that site, as PDF's make my old computer(web surfer only computer) act weird. But, it seem as though the oil is designed for the newer CAT eqiuped diesels so, the additive package is probably designed accordingly...Lower ZDDP/PHOS but, still higher Calcuim and other cleaners to control soot. Others in the know will chime in with better answers than I have.
 

uart

Thread starter
Messages
739
Location
Australia
Ok thanks guys, interesting info. So given that this particular oil is both energy conserving and low SAPS then I guess the difference is most likely just the detergent package.
 
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Messages
10,912
Location
Cincinnati, OH, USA
The oil you have up is SM rated, and it also has the (fairly rare) GM Dexos 2 diesel spec-as long as it is approved for the engine you are using it in it should work fine. Here in the USA many fleets use HDEO in everything!
 
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